Compact Energy Storage Device for Electromagnetic Launchers of Solids

Numerical study has been performed to investigate the operating characteristics and modes of an energy storage device based on a pulsed magnetohydrodynamic generator and a step-up transformer with a stored energy of 25 and 50 MJ and a secondary winding current of 250 kA at the final stage of operation. The operating parameters of such storage devices with rail launchers operating in the mode of rapid-fire launching of several projectiles were calculated.     

Fine structure of faces and imperfection of surface layers of shaped sapphire crystals

The development of faces on cylindrical and ribbon-shaped sapphire single crystals grown from a melt using the Stepanov method is investigated by optical and electronic microscopy. The crystallographic indices on the detected faces are established, and the microstructure of the growth layers is studied. The X-ray spectral microanalysis of foreign particles on the sapphire surface confirms the presence of molybdenum single crystals on it. Cathodoluminescence spectra of surface layers of sapphire single crystals are obtained.     

Turbulence Scales of the Monin–Obukhov Similarity Theory in the Anisotropic Mountain Boundary Layer

Russian Physics Journal - The characteristics of turbulence over mountainous terrain are investigated with an aim to predict propagation of short-wavelength electromagnetic waves (including optical...     

Effect of lead doping in the system Bi-Sr-Ca-Cu-O on the formation of 2212 crystals, grown from a KCl flux using pre-synthesized compounds (precursors)

A combination of the solution-melt method and solid-phase synthesis of complex oxides has been used to obtain crystals of Bi₂Sr₂CaCu₂O₈ (2212). Partial substitution of bismuth by lead leads to a change in the orientation of the growth layers in the (001) plane of the 2212 crystal which has an orthorhombic lattice. An increase in the dimensions is noted along with an enhancement of the quality of the crystals when lead is introduced into the composition of the precursors. Fiz. Tverd. Tela (St. Petersburg) 39, 219–221 (February 1997)     

Electron density distributions in substituted 2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-dienes studied by NMR spectroscopy

The signals in the¹³C NMR spectra of 2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-dienes (R¹=R²=H, Me,cyclo-C₃H₅, SiMe₃, SnMe₃, R¹=Me, R²=H, Cl) were completely assigned using 2D NMR spectroscopy. The pattern of the variation of the chemical shifts in the¹³C NMR spectra indicates that the effects of substituents R¹ and R² on the heterocycle and on the phenyl groups are of inductive rather than mesomeric origin and include the direct through-space polarization of bonds (field effect). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1962–1965, November, 1997.     

Method of calculating surface disturbances over a point source and a dipole

Formulas for calculating the deviations of the free surface of a heavy fluid in steady flow past a point source and a point dipole are derived. Examples of numerical calculations made in accordance with these formulas are presented.     

Electrochemical study of redox properties of 2,3,4,5-tetraphenyl-1-heterocyclopenta-2,4-dienes Ph4C4ER1R2 (E = Si,Ge, Sn). A new method for generation of tetraphenylgermole dianion

The electrochemical behavior of the sila-, germa-, and stannacyclopentadienes (metalloles) was studied by cyclic voltammetry. The oxidation and reduction mechanisms of these heterocyclic compounds were investigated. A new method for generation of tetraphenylgermole dianion involving the electrochemical reduction of the corresponding dichlorogermole is proposed. Electrochemical oxidation of the metallole dianions was first studied taking tetraphenylgermole dianion as an example.     

Penetration of electromagnetic field through the La-Er-Ba manganite far above the magnetic phase transition temperature

Using the technique of penetration of electromagnetic waves through the bulk samples of La_0.60Er_0.07Ba_0.33MnO₃ manganite, it is shown that in this class of strongly correlated materials the local dynamic magnetic ordering is preserved at the temperature by 66 K above the Curie temperature where the static long-range magnetic order is absent. In this temperature range the dynamic magnetic permeability exceeds unity and is frequency dependent. The average lifetime of local ordered states is estimated.